Artificial rubber dispersion and method of preparing the same



Patented July 2,1935 a n g I -j 2,006,s4i i i 7 ARTIFICIAL"RUBBER DISPERSION AND;

METHOD or rRErAnmG THE SAME I Edward Gran-triage, Stow, Ohio, assignor to The B'. F. Goodrich Company, New York, a

corporationiof New York 4 V NoiDrawing. ApplioationSeptember 2, 1933,

,. 5' SeriaLNo. 688,063 r e sc aims." 01, 134 -11) g 'Thisinvention relates to aqueous dispersions kali'metal ierro-land ierri-cyanides, particularly" V of rubberor like substances and has for its sodium andpotassiumferroand ferri-cyanidag, principal objects the preparation of artificial which salts are substantially neutral, 'and,read-- 7 rubber dispersions possessing superior qualities ily soluble in water,"and which ionize to furnish,

* 51such as a high degree o f stability Land asubsta'nrespectively tetra-valent and. tri-valent'hnega-y 517 tial absenceof 'odon aswell asthe provision of tively charged ions. r 1' y 11 a new ":method whereby such :dispersio'ns may While it .is frequentlyodesirable;to prepare pbe'producedeconomically. artificial dispersions ofcrude orreclaimedrub-m This invention consistsessentiallyin dispersb81321) is more Often necessary in commercial;- ing rubberwith the: aid of a substantiallynem I worktor prepare such dispersions, of compoundedjlfly;

, tral peptizing agent capable of ionizingin soluor pigmentedrubber. compositions, andzb way tionto" furnish polyvalent negative ions. of example the present invention will, now be; According to the methodof the present invendescribed as applied to'the preparation Offir, tion, vlllbbelif tbbe dispersed is plasticized' by' dispersion :of sucha' composition. v 7

l5 'masticationin 'conventional apparatus such as A, rubber composition containing 350.6 parts 5::

' afrubber mixing-mill oraniinter'nal mixer of byweightnoficrude rubber, 100.0 parts of re-,

thetype commonly used for suchwork in the claimed rubber prepared from scrap-innentubes; rubber" industry, and a quantity, usually about by the familiar-"heater process, 5.6 parts of five per cent; 'by weight; withrespect"to the' organicaccelerator, 20.0 parts z'inc;oxide,490.0

rubber; of a suitable dispersing agent is thorpartsjof "inorganic pigment or filler, and 33.8 20

oughly' mixed intotheplasticizedrubber. Mono? parts of a suitable softener, is thoroughly mixed.

, valent soaps of I oleic acid suchas potassium in the usualmanner. If. the mixed batch :isxnot ole'atefsodium oleate, diethylamine oleate, amalready sufficientlyplastic, or if it hasfbeenzin,v moniunioleate, triethanolammonium oleate, etc. storage, VitYiSQSHbjBCtGd JO further-masticationmenswmany effectiyeand'preferred dispersing beforenproceedingwithIthe-preparation of thef25.-

agents although 'other'soaps su'chas the corre- A dispersion. The amount of masticationyneces sponding stearates, as well as; otherdispersing saryv to reducertheprubber to therequired plastic agents now' used in" sirnilar processes including condition will yary'according to the particular, colloidal clays, glue casein, etc. may be emgrade crude. rubberused, thecompo'sition' ofrthe 1 ployed, The soaps may be added to the rubber rubber compound, and other factors including 30' as such, or suitable complementary reagents temperatures, the type and size of :masticator may be mixed into the rubber and allowed to employed, etc. but one familiar with the prepareact and form the soap in situ. Thereafter ration of artificial rubber dispersions will be able water is gradually worked into the mixture to to determine when the composition has been form a water-in-rubber dispersion to which is plasticized sufiiciently. To 1000 grams of the 35 added apeptizing agent of the type hereinabove plastic composition, is, then added, with conmentioned which causes the phases of the distinued mechanical working, 7.0 grams of solid persion to invert and produce a dispersion of potassium hydroxide, followed, after the alkali rubber in water] It is not necessary to defer has been workedinto the rubber, with sufficient 40 the addition of the peptizing agent until after water (about 10 to 20 c. c.) to dissolve the alkali, 40

- a quantity of waterhas been dispersed in the and 35.2'grams of oleic acid. When the soaprubber, but it maybe dissolved in and added forming ingredients have been thoroughly mixed with the water, in which case inversion of the into the rubber,r150 c. chof a 5%acqueous soluphases will occur when a sufiicient quantity of tion of potassium ferrocyanide are gradually v I the solution has been added and mixed into the added to thebatch still undergoing mechanical 45 rubber. V working. This quantity of peptizing-agent is I have discovered a new class of materials sufficient to cause the batch to invert and form which are particularly efiective'for use as'pepa dispersion in which the rubber. is in the dis- I tizing agents in the above. described process. persed phase, although the mixtureis not fluid,

, As has been indicated, this class comprises but more nearly 'theconsistency of putty. The 50 water-soluble compounds capable of ionizing in plastic mass so produced then is diluted with an solution to furnish polyvalent negative ions and additional 100 010. of the 5% potassium ferrowhich upon hydrolysis produce. a substantially cyanide solution to produce a more nearly fluid neutral or only slightly alkaline solution. Pre-c, dispersion which may be further diluted with ferred examples of such materials are: the alwater after its removal from the mixing appa- 55 ratus to produce a flowable dispersion of a desired concentrationand viscosity.

The product of the present invention exhibits numerous desirable properties. It is substantially free from objectionable odors; it does not exhibit a tendency to skim over'up on standing in water; exposed to-theaatmosphereyin' the pasty; condilh' e o mprises thoroug tion it does not dry rapidly thus permitting the m x n ru e n i p s agent and" then inclusion in a succeeding batch of waste remain: adding to the mixture with additional mechaniing in the dispersing apparatus from a preced wo ng a qu y of Water d Of a Wate 10 ing batch; andit is somewhat; cheaper? to -prefubl -r m in agent cted 'Om the Class pare than are prior dispersions; consisting of alkali metal ferrocyanides and The term"rubber is usediin thespecification alkali metal ferricyanides sufiicient-to invert the and claims in a generic sense. toiinclude comj u e d o fomrf diSDBTSiOII of rubber in pounded or uncompounded"caoutchouc, guttaiwater'; v g

percha, balata, and like natural or synthetic 6. The method which comprises intimately gums or resins. t V mixing: rubber-and; dispersing agent and then Although the present invention has been de adding-"to the mixture with additional mechani scribed in some detail with reference to a specific cal orkinga quantity of water and of a peptizexample illustrative of the invention, it is to be 'ing agent: selected from theclass consisting of 29 unqrstbdd t at; changes" b ade: inf. the theeferroiezandierriwyanidesof sodiumand po- 'deseribed procedure and 'that equivalent? mate =tassiumi'sufiicient' toinvert the mixture and'tor rialsmaybe' substitutedaforgthose mentioned ormg i dispersion 0 u Wa e a without departing from thespirit and scoperof: 7 ""IJoe'method'- which: comprises mixing intoxh the-invention as defined in the-appendedclaims. rubber'a:quantity'of'a monovalent soap and then; 25

I claim: t '7 a adding: with" continued mixing. a quantity of; LThe; method of. dispersing rubber in an water andiofa substantially neutral water: sol

persing agent into rubber and then adding sufficient water and substantially neutral water soluble peptizing agent capable of ionizing in solution to furnish polyvalent negative ions to invert the mixture and to form a dispersion of rubber 5 aqueous dispersionmedium which co1nprises.dispersing the aqueous r'nedium in the rubber and? 30" tlien' inverting the :phases of theidispersi'on byuble peptizing agent capable of ionizing1insolu.- tion; to? furnish poly/valent negative: ions suflicient to invert" the; mixture and to; form a dis-i 30! pelSlOIli of: rubber-in water. v V

The: method which comprises mixing. into rubberca quantity-of: a monovalentsoap and then: adding: withr'continuedmixing a quantity of waterdand" or a Water-solublepeptizing agent. selected from the :-classconsisting ofalkali metal ferrocyanides andzalkali metal ferricyanides sufqficient; to invert the: mixture" and vto form? a-dispersion ofrrubber :inwater; I I

9:"I he; method which: comprises mixing into rubber a. quantity-of a vmon ovalent soap.- ands then; addingqwith continued? mixing a quantity ofwater: and of: a :peptizing, agent selected from the: class:- consistingof the: ferroand ferri-cya--- nides 'of: sodium and potassiumsufiicient to. invert 21i themixture and'to-formea' dispersion of" rubber inawater.

admixing f therewith a substantially neutralwateri-soluble'peptizing:agent-capable of ionizing in solution-to furni'sh .polyval'en't negative ions.

2. The method of dispersing rubber in an 355 2 aqueousidis'persiorr medium WhiCh". comprises" dispersing the'iaqueous medium in the rubberi and then: inverting the phases of the dispersion'iby admixing; therewith a: water-soluble peptiz'inga agentisele'cted from; the class consisting of alkali -nmetal ferrocyanides and: alkali metal's 'ferricyanidesti 3:"J3he5metliodfof: dispersing: rubber in an; aqueous; dispersion medium which: comprisesdispersing 5 the": aqueous medium: in the" rubber" and izlthen inverting: the" phasesifof the dispersion by 'admixingi therewith a: peptizing agent selected fromlth'eiolasscconsisting of:theferroand ferricyanidestof sodium potassium.

V I I t EDWARD G: PARTRIDGE.

AijThermet'hodtwhich comprisesimixingiadis p 

